I'm having something strange here! The performance of queries that run against SYS objects like view DBA_OBJECTS , DBA_SEGMENTS, DBA_EXTENTS are VERY SLOWLY!! It's hang everytime and i need to kill the session and the PID process.

You have asked enough questions here to realize how important it is to provide Oracle version number and operating system information. I have seen some of the symptoms you describe under older versions of the database.

So - please provide Oracle version number and operating system information.

I have deleted SYS statistics but it didn't help so i have generated statistics again. The problem still happens. The only workaround here is to put hint RULE on query. I don't know what to do anymore.

Predicate Information (identified by operation id):
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1 - filter(BITAND("S"."XPFLAGS",8388608)=8388608)
2 - access("S"."OBJ#"=:B1)
4 - filter(((("O"."TYPE#"<>1 AND "O"."TYPE#"<>10) OR ("O"."TYPE#"=1 AND =1)) AND (INTERNAL_FUNCTION("O"."OWNER#") OR ("O"."TYPE#"<>11 AND
"O"."TYPE#"<>14 AND IS NOT NULL) OR (INTERNAL_FUNCTION("O"."TYPE#") AND IS NOT NULL) OR ("O"."TYPE#"=13 AND IS NOT NULL) OR ("O"."TYPE#"=11 AND
IS NOT NULL) OR ("O"."TYPE#"=12 AND IS NOT NULL) OR ("O"."TYPE#"=6 AND IS NOT NULL) OR (INTERNAL_FUNCTION("O"."TYPE#") AND IS NOT NULL) OR
("O"."TYPE#"=22 AND IS NOT NULL) OR ("O"."TYPE#"=14 AND IS NOT NULL) OR INTERNAL_FUNCTION("O"."TYPE#") OR ("O"."TYPE#"=33 AND IS NOT NULL) OR
("O"."TYPE#"=46 AND IS NOT NULL) OR ("O"."TYPE#"=62 AND IS NOT NULL) OR ("O"."TYPE#"=66 AND IS NOT NULL) OR ("O"."TYPE#"=48 AND IS NOT NULL)
OR ("O"."TYPE#"=44 AND IS NOT NULL) OR ("O"."TYPE#"=59 AND IS NOT NULL) OR ("O"."TYPE#"=23 AND IS NOT NULL) OR ("O"."TYPE#"=68 AND IS NOT
NULL) OR (INTERNAL_FUNCTION("O"."TYPE#") AND IS NOT NULL) OR ("O"."TYPE#"=42 AND IS NOT NULL) OR ("O"."TYPE#"=32 AND IS NOT NULL) OR
("O"."TYPE#"=81 AND IS NOT NULL) OR ("O"."TYPE#"=55 AND =1)) AND (DECODE("O"."TYPE#",0,'NEXT
OBJECT',1,'INDEX',2,'TABLE',3,'CLUSTER',4,'VIEW',5,'SYNONYM',6,'SEQUENCE',7,'PROCEDURE',8,'FUNCTION',9,'PACKAGE',11,'PACKAGE
BODY',12,'TRIGGER',13,'TYPE',14,'TYPE BODY',19,'TABLE PARTITION',20,'INDEX PARTITION',21,'LOB',22,'LIBRARY',23,'DIRECTORY',24,'QUEUE',28,'JAVA
SOURCE',29,'JAVA CLASS',30,'JAVA RESOURCE',32,'INDEXTYPE',33,'OPERATOR',34,'TABLE SUBPARTITION',35,'INDEX SUBPARTITION',40,'LOB PARTITION',41,'LOB
SUBPARTITION',42,NVL(,'MATERIALIZED VIEW'),43,'DIMENSION',44,'CONTEXT',46,'RULE SET',47,'RESOURCE PLAN',48,'CONSUMER GROUP',55,'XML
SCHEMA',56,'JAVA DATA',57,'SECURITY PROFILE',59,'RULE',60,'CAPTURE',61,'APPLY',62,'EVALUATION CONTEXT',66,'JOB',67,'PROGRAM',68,'JOB
CLASS',69,'WINDOW',72,'WINDOW GROUP',74,'SCHEDULE',79,'CHAIN',81,'FILE GROUP','UNDEFINED')='PACKAGE' OR DECODE("O"."TYPE#",0,'NEXT
OBJECT',1,'INDEX',2,'TABLE',3,'CLUSTER',4,'VIEW',5,'SYNONYM',6,'SEQUENCE',7,'PROCEDURE',8,'FUNCTION',9,'PACKAGE',11,'PACKAGE
BODY',12,'TRIGGER',13,'TYPE',14,'TYPE BODY',19,'TABLE PARTITION',20,'INDEX PARTITION',21,'LOB',22,'LIBRARY',23,'DIRECTORY',24,'QUEUE',28,'JAVA
SOURCE',29,'JAVA CLASS',30,'JAVA RESOURCE',32,'INDEXTYPE',33,'OPERATOR',34,'TABLE SUBPARTITION',35,'INDEX SUBPARTITION',40,'LOB PARTITION',41,'LOB
SUBPARTITION',42,NVL(,'MATERIALIZED VIEW'),43,'DIMENSION',44,'CONTEXT',46,'RULE SET',47,'RESOURCE PLAN',48,'CONSUMER GROUP',55,'XML
SCHEMA',56,'JAVA DATA',57,'SECURITY PROFILE',59,'RULE',60,'CAPTURE',61,'APPLY',62,'EVALUATION CONTEXT',66,'JOB',67,'PROGRAM',68,'JOB
CLASS',69,'WINDOW',72,'WINDOW GROUP',74,'SCHEDULE',79,'CHAIN',81,'FILE GROUP','UNDEFINED')='PROCEDURE' OR DECODE("O"."TYPE#",0,'NEXT
OBJECT',1,'INDEX',2,'TABLE',3,'CLUSTER',4,'VIEW',5,'SYNONYM',6,'SEQUENCE',7,'PROCEDURE',8,'FUNCTION',9,'PACKAGE',11,'PACKAGE
BODY',12,'TRIGGER',13,'TYPE',14,'TYPE BODY',19,'TABLE PARTITION',20,'INDEX PARTITION',21,'LOB',22,'LIBRARY',23,'DIRECTORY',24,'QUEUE',28,'JAVA
SOURCE',29,'JAVA CLASS',30,'JAVA RESOURCE',32,'INDEXTYPE',33,'OPERATOR',34,'TABLE SUBPARTITION',35,'INDEX SUBPARTITION',40,'LOB PARTITION',41,'LOB
SUBPARTITION',42,NVL(,'MATERIALIZED VIEW'),43,'DIMENSION',44,'CONTEXT',46,'RULE SET',47,'RESOURCE PLAN',48,'CONSUMER GROUP',55,'XML
SCHEMA',56,'JAVA DATA',57,'SECURITY PROFILE',59,'RULE',60,'CAPTURE',61,'APPLY',62,'EVALUATION CONTEXT',66,'JOB',67,'PROGRAM',68,'JOB
CLASS',69,'WINDOW',72,'WINDOW GROUP',74,'SCHEDULE',79,'CHAIN',81,'FILE GROUP','UNDEFINED')='SEQUENCE' OR DECODE("O"."TYPE#",0,'NEXT
OBJECT',1,'INDEX',2,'TABLE',3,'CLUSTER',4,'VIEW',5,'SYNONYM',6,'SEQUENCE',7,'PROCEDURE',8,'FUNCTION',9,'PACKAGE',11,'PACKAGE
BODY',12,'TRIGGER',13,'TYPE',14,'TYPE BODY',19,'TABLE PARTITION',20,'INDEX PARTITION',21,'LOB',22,'LIBRARY',23,'DIRECTORY',24,'QUEUE',28,'JAVA
SOURCE',29,'JAVA CLASS',30,'JAVA RESOURCE',32,'INDEXTYPE',33,'OPERATOR',34,'TABLE SUBPARTITION',35,'INDEX SUBPARTITION',40,'LOB PARTITION',41,'LOB
SUBPARTITION',42,NVL(,'MATERIALIZED VIEW'),43,'DIMENSION',44,'CONTEXT)
5 - access("O"."OWNER#"="U"."USER#")
7 - filter(("O"."NAME"<>'_NEXT_OBJECT' AND "O"."NAME"<>'_default_auditing_options_' AND "O"."LINKNAME" IS NULL))
8 - filter(("I"."TYPE#"=1 OR "I"."TYPE#"=2 OR "I"."TYPE#"=3 OR "I"."TYPE#"=4 OR "I"."TYPE#"=6 OR "I"."TYPE#"=7 OR "I"."TYPE#"=9))
9 - access("I"."OBJ#"=:B1)
12 - access("OBJ#"=:B1 AND "GRANTEE#"="KZSROROL")
filter((INTERNAL_FUNCTION("PRIVILEGE#") AND "GRANTEE#"="KZSROROL"))
13 - filter((((-"KZSPRPRV")=(-45) OR (-"KZSPRPRV")=(-47) OR (-"KZSPRPRV")=(-48) OR (-"KZSPRPRV")=(-49) OR (-"KZSPRPRV")=(-50)) AND
"INST_ID"=USERENV('INSTANCE')))
14 - filter((((-"KZSPRPRV")=(-184) OR (-"KZSPRPRV")=(-181)) AND "INST_ID"=USERENV('INSTANCE')))
15 - filter(((-"KZSPRPRV")=(-141) AND "INST_ID"=USERENV('INSTANCE')))
16 - filter(((-"KZSPRPRV")=(-152) AND "INST_ID"=USERENV('INSTANCE')))
17 - filter(((-"KZSPRPRV")=(-109) AND "INST_ID"=USERENV('INSTANCE')))
18 - filter((((-"KZSPRPRV")=(-144) OR (-"KZSPRPRV")=(-141)) AND "INST_ID"=USERENV('INSTANCE')))
19 - filter((((-"KZSPRPRV")=(-189) OR (-"KZSPRPRV")=(-190) OR (-"KZSPRPRV")=(-191) OR (-"KZSPRPRV")=(-192)) AND "INST_ID"=USERENV('INSTANCE')))
20 - filter(((-"KZSPRPRV")=(-181) AND "INST_ID"=USERENV('INSTANCE')))
21 - filter((((-"KZSPRPRV")=(-200) OR (-"KZSPRPRV")=(-201) OR (-"KZSPRPRV")=(-202) OR (-"KZSPRPRV")=(-203) OR (-"KZSPRPRV")=(-204)) AND
"INST_ID"=USERENV('INSTANCE')))
22 - filter((((-"KZSPRPRV")=(-251) OR (-"KZSPRPRV")=(-252) OR (-"KZSPRPRV")=(-253) OR (-"KZSPRPRV")=(-254)) AND "INST_ID"=USERENV('INSTANCE')))
23 - filter((((-"KZSPRPRV")=(-246) OR (-"KZSPRPRV")=(-247) OR (-"KZSPRPRV")=(-248) OR (-"KZSPRPRV")=(-249)) AND "INST_ID"=USERENV('INSTANCE')))
24 - filter(((-"KZSPRPRV")=(-265) AND "INST_ID"=USERENV('INSTANCE')))
25 - filter(((-"KZSPRPRV")=12 AND "INST_ID"=USERENV('INSTANCE')))
26 - filter((((-"KZSPRPRV")=(-222) OR (-"KZSPRPRV")=(-223)) AND "INST_ID"=USERENV('INSTANCE')))
27 - filter((((-"KZSPRPRV")=(-258) OR (-"KZSPRPRV")=(-259) OR (-"KZSPRPRV")=(-260) OR (-"KZSPRPRV")=(-261)) AND "INST_ID"=USERENV('INSTANCE')))
28 - filter((((-"KZSPRPRV")=(-177) OR (-"KZSPRPRV")=(-178)) AND "INST_ID"=USERENV('INSTANCE')))
29 - filter((((-"KZSPRPRV")=(-268) OR (-"KZSPRPRV")=(-267)) AND "INST_ID"=USERENV('INSTANCE')))
30 - filter((((-"KZSPRPRV")=(-265) OR (-"KZSPRPRV")=(-266)) AND "INST_ID"=USERENV('INSTANCE')))
31 - filter((((-"KZSPRPRV")=(-45) OR (-"KZSPRPRV")=(-47) OR (-"KZSPRPRV")=(-48) OR (-"KZSPRPRV")=(-49) OR (-"KZSPRPRV")=(-50)) AND
"INST_ID"=USERENV('INSTANCE')))
32 - filter((((-"KZSPRPRV")=(-205) OR (-"KZSPRPRV")=(-206) OR (-"KZSPRPRV")=(-207) OR (-"KZSPRPRV")=(-208)) AND "INST_ID"=USERENV('INSTANCE')))
33 - filter((((-"KZSPRPRV")=(-277) OR (-"KZSPRPRV")=(-278)) AND "INST_ID"=USERENV('INSTANCE')))
36 - filter(BITAND("S"."XPFLAGS",8388608)=8388608)
37 - access("S"."OBJ#"=:B1)

Querying DBA_OBJECTS produces a much more compact plan that executes faster: